Ink adhesion is the fastness of ink adhesion to the printing surface, if poor adhesion and fixation is not good, there is no certain fastness, not resistant to friction, not resistant to impact, not resistant to fatigue, that is, there is no printing.

There are five test methods for testing ink adhesion fastness:

1) scratch resistance test.

Apply moderate pressure with the fingernails of the thumb and repeatedly scrape the ink layer that has been printed and dried on the film. If the ink layer is scratched or the ink falls off, the adhesion of the ink is not ideal.

2) Tape peeling test.

Use viscose tape to evenly stick to the printing sample, press it with your fingers on the back of the tape to make it stick firmly, and then hold both ends of the tape with your hands to pull up at a medium speed to observe the ink sticking up by the tape.As long as there is ink on the tape, it shows that the adhesion of the ink on this kind of printing material is not good.

3) dry friction test.

The printing surfaces of the two samples are stacked together relative to each other, applying a pressure of 2 to 4 pounds of repeated friction, and scratches or ink shedding indicates poor ink adhesion.

4) the wet friction test method is similar to the above dry friction test, except that a little water needs to be added between the two prints.

5) Test of detergent resistance.

Drop one or more drops of alkaline detergent on the printing sample, suck it clean with paper towels or clean soft cloth or clean soft cloth after 15 seconds, and then wipe it with medium pressure. If there is any change in the printed picture and text part, it indicates that the adhesion of the ink is not good.

If you want to improve your ink adhesion, pls contact us. We would like to give you some suggestion.